Srilm wrote:
Irish Drifter wrote:
I know you are aware of this but you forgot to point out that is why pilots have not only seat belts but a combination which includes a shoulder harness.
Good point. Why don't passenger seats have shoulder harnesses? Good question. I'd wear it if they had one. It's safer.
SR
A few reasons that I can think of...
1) cost - of course it's always one factor for the airlines. Shoulder harnesses are worth around $1500 each and the inertial reels about $500 each as opposed to $400 or so for a lap belt.
2) An improperly adjusted shoulder harness can do more harm then good in an accident, while a lap belt is super easy to adjust. One of my pre-flight routines when I'm taking the observers seat in the cockpit is adjusting the various belts. PITA when some skinny flight attendant sat in it last, lol.
3) You can't get people to wear lap belts half the time. Imagine the frustration FA's would have trying to get 300 people putting on harnesses and then having to check them for fit afterwards.
4) A shoulder harness needs a solid mounting point for it's two shoulder belts and inertial reels. Passenger seats are designed to break over in a crash. One 3 person seat bench in coach weighs about 50-75lbs depending on the shit added to it. One crew seat that has a harness and the structure strong enough to support it weighs about 100 lbs EACH. You can have an airplane where everyone has a 5 point harness but can't fly anywhere because it's too heavy or.... you get the point.
As for safety... don't knock the simple old passenger seats. Airplanes made before 1988 (iirc) have seats that can withstand 9G's of crash force in a forward direction. Later regs raised that to 16G's IMO, the shoulder harnesses are not just a means to give the pilot a better chance at surviving a crash but are more there to let them be able to maintain control in an upset aircraft condition like turbulence or loss of attitude control.
There's been many crashes where passengers survived in their seats while the rest of the aircraft was in a million pieces.